From Baffin Island to New Orleans.

SEVERAL YELLOW JACKET WASPS were sighted in Arctic Bay, a community of 700 people on the northern tip of Baffin Island at more than 73 degrees North latitude, during the summer of 2004. Noire Ikalukjuaq, the mayor of Arctic Bay, said he knew no word in the Inuit language for the insect.

In Kaktovik, Alaska, a village on the Arctic Ocean, a robin built a nest during the summer of 2003--not an unusual event in more temperate latitudes but quite a departure where, in the Inupiat language, no name exists for robins.

During the summer of 2004, hunters found half a dozen polar bears that had drowned about 200 miles north of Barrow, on Alaska's northern coast. They had tried to swim for shore after the ice had receded 400 miles. A polar bear can swim 100 miles--but not 400.

Global warming is leaving its evidentiary trail in melting ice as well as in the heating of the seas. The wrath of intensifying hurricanes and typhoons stoked by warming oceans has already devastated parts of the subtropics. The yellow jacket, the robin, the drowned polar bears, and the hurricane triplets--Katrina, Rita, and Wilma--are harbingers of an ominous future.

The Inuit can empathize with the people of New Orleans. You probably haven't seen Inuits on the evening news, but some hunters have died after falling through unseasonably thin ice. Sheila Watt-Cloutier, president of the Inuit Circumpolar Conference, testified before the Senate Commerce Committee hearing on global warming on August 15, 2004. She said the Inuits' ancient connection to their hunting culture may disappear within her grandson's lifetime, as the melting ice makes it difficult for them to get to their traditional hunting and harvesting areas.

"My Arctic homeland is now the health barometer for the planet," she said. "We are an endangered species."

When I first met Watt-Cloutier in Iqaluit during the summer of 2001, she was just beginning to tackle global warming. Now she takes her case to international diplomatic and scientific forums. Equally at home in ornate conference halls and in a small boat hunting seals with other Inuit near Baffin Island, Watt-Cloutier leads about 155,000 Inuit who are struggling to maintain some semblance of tradition in a swiftly changing, melting, and often polluted Arctic homeland. She has the delicacy of a diplomat, the precision of a scientist, and the verve of a social activist.

In her spacious house overlooking Frobisher Bay, she serves visitors some of the best Arctic char sushi on the planet, along with an urgent message: "Protect the Arctic and you will save the planet. Use us as your early-warning system. Use the Inuit story as a vehicle to reconnect us all so that we can understand the people and the planet are one."

Climate change in the Arctic is accelerating year by year. During the summer of 2004, compared to the previous year, enough Arctic ice to blanket an area twice the size of Texas melted. The same trend continued this summer. In the past, weak-ice years often were followed by years in which ice was restored. This kind of balancing hasn't been occurring recently.

"If you look at these last few years, the loss of ice we've seen ... is rather remarkable," says Mark Serreze of the National Snow and Ice Data Center at the University of Colorado. Scientists now talk seriously of an ice-free Arctic in the summer. The main point of debate is how soon this will happen.

In January 2004, Watt-Cloutier sent me an e-mail from Baffin Island: Frobisher Bay had just frozen over for the season at a record late date. "We are finally into very 'brrrrrr' seasonal weather, and the bay is finally freezing straight across," she wrote. "At Christmastime, the bay was still open and as a result of the floe edge being so close we had a family of polar bears come to visit the town a couple of times." The previous Christmas, rain had fallen in Iqaluit, an unprecedented event.

Two weeks before writing me, Watt-Cloutier was representing the Inuit at a U.N. conference on climate change in Milan, Italy. "Talk to hunters across the North and they will tell you the same story--the weather is increasingly unpredictable," she told the gathering. "The look and feel of the land is different. The sea-ice is changing. Hunters are having difficulty navigating and traveling safely. We have even lost experienced hunters through the ice in areas that, traditionally, were safe! ... Our elders, who instruct the young on the ways of the winter and what to expect, are at a loss."

It's about 4,000 miles from Baffin Island to New Orleans. But the same phenomenon that is threatening the Inuits' way of life may have wreaked havoc on the Gulf Coast.

Hurricanes are heat engines. They live and die according to the warmth of the water over which they move. Although other factors were involved, one important reason why Katrina, Rita, and Wilma blew up so quickly into three of the six most intense hurricanes in U.S. history was the temperature of the Gulf of Mexico and surrounding seas, 88 to 90 degrees at summer's peak, 2 to 4 degrees above recent averages.

Water temperatures vary for reasons other than global warming. Atlantic hurricanes intensify in twenty to thirty year cycles, following changes in water temperature. We are presently in the active phase of such a cycle, aided by generally rising air and water temperatures. Thus, the number and intensity of hurricanes over Florida and the other Gulf Coast states have been unusually high during the past several years. Hurricanes also intensify under calm high pressure in the upper atmosphere, which reduces wind shear that tears them apart.

Shortly after Katrina pounded the Gulf Coast, P. J. Webster and colleagues, writing in Science, linked rising water temperatures directly to the number, duration, and intensity of tropical cyclones. The researchers found that the number of storms in the two most powerful categories, 4 and 5, had risen to an average of eighteen a year worldwide since 1990, up from eleven in the 1970s. Other studies assert that Webster and colleagues, by going back only to the 1970s, missed a cyclical peak in numbers of hurricanes during the 1960s. The argument about an increase in intensity, however, has stood up to scrutiny.

In addition to cycles in hurricane activity and warming temperatures, the coastline marshes of the Mississippi Delta that once afforded the coast some protection have been subsiding for decades, mainly because water and oil have been pumped out of the ground. The Mississippi Delta also has been laced with oil companies' transport canals, further weakening the coastline.

Each severe hurricane compounds these long-term trends. Most of Katrina's damage resulted from storm surge and flooding, rather than wind. Hurricane Camille's winds were stronger than Katrina's, but thirty-six years ago the storm surge did not reach many areas that were wrecked this year. This may be because as ice melts around the world, sea levels are slowly rising. Warmer water also expands and occupies more space.

Since 1900, sea levels have risen 12.3 inches in New York City, 8.3 inches in Baltimore, 7.3 inches in Key West, 22.6 inches in Galveston, and six inches in San Francisco. The rate of increase has been accelerating over time. (The wide range results from the rising or falling of the land itself. San Francisco is rising; the East and Gulf coasts are subsiding.)

Many scientific studies have forecast that the sea level may rise between eight and twenty inches during the twenty-first century, making life on the East and Gulf coasts of the United States precarious.

All of these factors are cumulative. In coming decades, temperatures will be higher, on average, than today. Hurricanes, when they occur, will be more severe, and the land will have subsided substantially. We can expect intensifying climate calamities, as millions of environmental refugees flee their low-lying homes with the approach of each season's storms.

Among scientists who follow the pace of global warming, I anxiety has been rising that the Earth is reaching (or may even have passed) a "tipping point," with the effects of greenhouse warming surpassing any foreseeable human ability to contain or reverse it.

Sir John Houghton, one of the world's leading experts on global warming, told the London Independent: "We are getting almost to the point of irreversible meltdown, and will pass it soon if we are not careful."

"The climate is changing much more quickly than scientists had projected only a few years ago," says Ross Gelbspan, author of The Heat Is On and Boiling Point. "We are seeing impacts--accelerating migrations of species, the thawing of the Siberian and Canadian tundra, the drying of the Amazon rainforest--that researchers did not expect to see until near the end of the twenty-first century. As a result, scientists are concerned about natural systems crossing invisible thresholds and taking on their own irreversible momentum."

As Arctic ice melts, darker-colored water absorbs more heat. Thawing permafrost adds greenhouse gases to the atmosphere, as do the increasing numbers of wildfires (especially those which burn underground stores of peat).

Carbon dioxide levels in the atmosphere also are rising, fed by, among other things, the increasing fossil-fuel use in the United States and other countries, slash-and-burn agriculture ill places like Indonesia and Brazil, increasing wildfires, as well as rapid industrialization using dirty coal in China and India. Rising levels of carbon dioxide in the oceans will be making them more acidic, causing the calcium-carbonate shells of marine animals (such as corals and plankton) to dissolve.

In August 2005, climate researchers reported that a large area of western Siberia was undergoing an unprecedented thaw that could dramatically increase the rate of global warming, as melting permafrost injects additional carbon dioxide and methane into the atmosphere. Permafrost across a million square kilometers, an area as large as France and Germany combined, has already started to melt, reported Sergei Kirpotin at Tomsk State University in western Siberia and Judith Marquand of England's Oxford University. What was until recently a barren expanse of frozen peat had turned, during the summer, into a broken landscape of mud and lakes, some more than a kilometer across. Kirpotin told the Manchester Guardian Weekly that the situation was an "ecological landslide that is probably irreversible and is undoubtedly connected to climatic warming."

By the end of this century, temperatures may reach a level that may melt solid methane in the oceans. During past periods of rapid warming, tens of millions of years ago, methane in gaseous form (called "clathrate") has been released from sea floors in intense eruptions, following an increase in temperatures of up to 8 degrees Celsius, which is within the range projected by many climate models for the end of this century. Scientists call these explosions the "clathrate gun" or "methane burp." Once such reactions begin, they feed themselves, dramatically accelerating the rate of warming in the atmosphere.

Will humankind be able to dodge this bullet? If so, how? The short answer, according to many scientists, is to cut fossil fuel consumption by about 70 percent within the next fifteen to twenty years. That's what would be required to stabilize greenhouse-gas levels in the atmosphere before natural feedbacks begin to accelerate warming beyond control.

Such swift action is not likely. Evidence of warming reveals itself to us in a forty-to-fifty-year feedback loop. We are feeling warming now in response to the fossil fuels that were burned in about 1960. Since then, world consumption has risen several times over.

Increasingly efficient use of energy and diplomatic action are beginning to slow the rate of increase in greenhouse gases worldwide, however. "The growth rate ... peaked near 1980," according to James Hansen, director of the Goddard Institute for Space Studies, writing with Makiko Sato in the Proceedings of the National Academy of Sciences.

In Denmark, for example, most families now own a share of a wind turbine. Some areas of Germany derive a substantial proportion of their energy from wind and solar power. In Spain, building codes have been amended to require use of passive solar power. Hansen and many other experts warn, though, that these changes are not sufficient and that the window of opportunity is narrowing with each passing day.

The Inuit are not waiting. Watt-Coultier and the Inuit Circumpolar Conference have assembled a human rights case against the United States. They have invited the Washington-based Inter-American Commission on Human Rights to visit the Arctic to witness the devastation being caused by global warming.

While the commission is not a tribunal that can issue binding verdicts, a finding in favor of the Inuit against the United States could become useful evidence in future attempts to successfully sue the United States on climate-change grounds in international legal forums.

"We want to show that we are not powerless victims," says Watt-Coultier. "These are drastic times for our people and require drastic measures. The Earth is literally melting. If we can reverse the emissions of greenhouse gases in time to save the Arctic, then we can spare untold suffering."

Illustration by Alex Nabaum

Bruce E. Johansen, Frederick W. Kayser Professor of Communication at the University of Nebraska at Omaha, is author of the forthcoming "Global Warming in the 21st Century. "He wrote "Arctic Heat Wave" for The Progressive's October 2001 issue.